New Glomex directional TV antenna

Well... if it actually works, it's money better spent than the crappy frisbee they put on there now. I was just wondering how well it performed, especially on the UHF bands, compared to the omni one...
 
Have you seen a new HDTV connected to the Glomex? I just bought a 19" flat panel with DVD to replace the old Panasonic with VHS unit in the salon since 2/09 is approaching. I connected it the the old-style roof-mounted, actually in my attic, antenna at my house. I haven't used it in 10 years since we've had satellite. Wow! Connected to the old style antenna I got about 35 stations. The regular analog TV would get 8-10. I heard that you would get more stations, but I was skeptical. I can't wait to hook it up in the boat.

I'll report back on the results at the lake.
 
They have to broadcast in HD not analog. A number of stations are already broadcasting in HD. The old analog sets will work with a converter box.
 
ATSC channels are on the same frequencies as current TV (many are on UHF). Any existing decent TV antenna can receive the same channels. The only thing 'special' about HD channels is the greater susceptibility to interference. While you can 'watch' a crappy analog signal full of ghosting and static, HD is a lot more finicky. It's usually an all-or-nothing proposition. People in fringe areas, like oh, say, boats in a marina, will probably not see improvements in reception.

To watch HD on your current TV you'll need to add an ATSC converter. It'll convert the signal from over-the-air HD to RF, composite video or s-video (this varies on different boxes). Just like in the old days of using a cable-ready VCR as a tuner for a non-cable-ready TV. I haven't found a decent 12v converter box. Many are either not 12v, do a crappy job or are too large for where I'd want to mount it. But I'm guessing the situation will improve and the RV market will certainly have some affect on it.
 
Just my 2 cents. Are your TV's HD? A friend with the same crappy UFO antenna as half the boats at my yacht club just hooked up a new HD flatscreen to his old style UFO and he is getting the multiple HD local channels perfectly.
Chris
 
I was asking the question about that antenna for the UHF/Digital reception capabilities and what improvement one would expect (or has seen) by having a directional antenna.

The broadcasts for the ATSC tuners and the mandatory conversion is for Digital TV (DTV) and does not necessarily mean HD. I hear people say there is a "mandatory coversion to HD" and that is just not true. In fact, some of our stations in this area are broadcasting in SD (standard definition) over the DTV signal. There is nothing wrong with that but don't assume everything will be HD as it won't. Actually, there is some advantage for a station not to be in HD as they can broadcast multiple SD channels over the same spectrum they are being allocated instead of a single HD feed. You will still be buying small LCD TV's that are not HD (like 480p) and have ATSC tuners and they'll do just fine. They are just now starting to come out with 15" LCD's that can do minimal HD (720p)... I've seen only one and it was by ViewSonic. The 19-30" family of LCD's seem to all be 720p right now and we are just seeing a few 1080p ones come out.

The DTV signals are being broadcast over the UHF spectrum and the Glomex antennas do a decent job of picking up UHF analog channels (I can pick up Richmond 40 miles away) so they should do fine at picking up the DTV broadcasts. The omni-directional/UFO antennas are crap though for picking up the VHF channels and that's what everyone really complains about. However, the directional aspect of that new fangled Glomex is interesting as it would be like adjusting the "circular UHF" antenna on the back of a TV if any of you remember doing that... remember how you have "rabbit ears" for VHF and that circular antenna for UHF? This would be like adjusting the circle for like channel 33... I would think it would help out for fringe areas but heck... I don't know... that's why I posted the question..

Boaters will see an improvement because Channels 2-13 will now be essentially broadcast on a frequency (UHF) that the crappy Glomex performs well on.

I'll find out the "facts" soon.. I'm installing a new AV system on Four Suns over the next 2 weeks... the inside of it is a mess at the moment... but it'll be pure awesomeness when finished.
 
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Gary and all,
Thanks for providing more info about this subject, at least to me. I can see where Gary wrote about DTV, SD, etc. ABC in Chicago is Channel 7. I have 3 channel 7s pop up with different programming. A box on the screen had 7-SD, 7-HD, and I can't remember what the 3rd channel 7 was.
 
Probably some improvement. Depends on what you're seeing now. The gain figure is 3db to 6db. Nothing spectacular, but the 60 degree directionality is a pretty good figure for such a small antenna. If your problem is ghosting, this certainly will help. If your problem is low signal strength, the gain and amplification might help. The key with antennas with rotors is that you can use more RF gain for signal acquisition without also degrading the image quality because reflected images (ghosts) are ignored.

The problem with TV reception at marinas is that if you're not close to the transmitter, an antenna down close to sea level just can't see the transmitting antenna for the line-of-sight VHF/UHF signal because of higher terrain between the transmitter and the boat. That fundamental problem is tough to overcome with any antenna, unless you want to fly it from a kite or balloon.

Best regards,
Frank
 
I am glad "Four Sons" clarified this conversion for all to read. I have seen so many threads that are confusing readers indicating the conversion the industry is going thru is ANALOG to HIGH DEFINITION. This is simply NOT TRUE. The conversion is ANALOG to DIGITAL.
 
davefin said:
I am glad "Four Sons" clarified this conversion for all to read. I have seen so many threads that are confusing readers indicating the conversion the industry is going thru is ANALOG to HIGH DEFINITION. This is simply NOT TRUE. The conversion is ANALOG to DIGITAL.
Click to expand...

At things stand currently, there appear to be two ways to go if you have a decent antenna and an analog TV. There is a thread going on another forum under the mechainical/electical section. The two practical fixes are to install a very small inverter to power converter boxes which tend to be 110 volts (so you don't have to run your genny to watch a 12 volt flatscreen). You plug the converter into the inverter, cut your coax antenna and plug that into the "Ant/In" and plug the other end into the "Ant/Out" and you should be in business. The other approach is more appealing and that involves using a 12 volt converter box and doing the same thing minus the inverter. An install using this approach is going on now with a promise to post the results including the brand name of the box. If that goes well, it seems to me to be a very clean and simple solution for converting digital over the air signals to analog signals that your TV will display.
 
There are three key issues with digital over analog. The 8 level VSM modulation used for ATSC is more efficient for long distances while requiring less power than NTSC. Also ATSC is trellis encoded with error detection and correction, which helps with push data rates up while making the data stream more robust. Also numerical filtering of the data stream helps to eliminate multipath noise. Might be worth trying an ATSC tuner instead.

Regarding antennas, I remembered some stuff from long ago. I use to install antennas to earn some extra money when I was in school. Here's an overview that hits the basics. If I remember right, a deep fringe antenna that was good for about 100 miles from the transmitter had about about 10 dB of gain (less on lower channels) and a directionality of about 30 degrees.

Best regards,
Frank C
 
sbw1 said:
The other approach is more appealing and that involves using a 12 volt converter box and doing the same thing minus the inverter. An install using this approach is going on now with a promise to post the results including the brand name of the box. If that goes well, it seems to me to be a very clean and simple solution for converting digital over the air signals to analog signals that your TV will display.
Click to expand...

Here's one list of boxes:
http://www.ezdigitaltv.com/Additional_Features_Matrix.html

These look interesting:
http://www.ezdigitaltv.com/Artec_T3A_Pro.html
http://www.ezdigitaltv.com/Tatung_TDB3001.html
http://www.ezdigitaltv.com/Zentech_DF2000.html

The zentech unit supports zooming which may be useful for avoiding portions of a 16:9 program being clipped on a 4:3 TV. All the 12v units appear to support only composite video or RF (not s-video or component rgb). Probably not a big deal for most boat TVs.
 
wkearney99 said:
Here's one list of boxes:
http://www.ezdigitaltv.com/Additional_Features_Matrix.html

These look interesting:
http://www.ezdigitaltv.com/Artec_T3A_Pro.html
http://www.ezdigitaltv.com/Tatung_TDB3001.html
http://www.ezdigitaltv.com/Zentech_DF2000.html

The zentech unit supports zooming which may be useful for avoiding portions of a 16:9 program being clipped on a 4:3 TV. All the 12v units appear to support only composite video or RF (not s-video or component rgb). Probably not a big deal for most boat TVs.
Click to expand...

Why would you worry about supporting video since the DVD and other media bypass the converter box and are feed from the preamp and run directly to the TV monitor? The converter would only handle off air digital signal and not process the other signals that are already digital. At least it appears to work that way on my install.
 
I hate Glojunk. I spend more freakin time trying to get it to work than anything else on the boat. I hate it so much, that I refuse to buy anything from that company EVER. I finally bought a pair of rabbit ears and they work 10 times better than the Glowcrap antenna.

I've been dumping stuff onto my iphone and watching that on my TV.

Oh, Frank C, i need to talk to you about the firewireSDK and coming up with a better
way to work that whole thing. I kind of got it to work, but not really.
 
TurtleTone said:
Oh, Frank C, i need to talk to you about the firewireSDK and coming up with a better
way to work that whole thing. I kind of got it to work, but not really.
Click to expand...

No problem, Mike. I'm a consultant. Like any whore, I work for anyone and do anything as long as the money is right. However, unlike the hooker, if won't feel good for you.

Here's a freebee. Did you buy the Quicktime Pro MPEG 2 extension? It's $20. Cheaper than a hooker.

Best regards,
Frank
 
I don't know anything about hookers.

I do have the quicktime pro mpeg2 codec, but it doesn't recognize that damn m2t file. maybe i'm not using the right SDK build. I tried the AVCapture thingamabob, looked like it was recording, created an m2t file. I got a new cable box and now it's not working. uuuhhg.

are you using quicktime to playback the m2t file? or are you using something else?

sorry for hijacking the glowjunk thread.

Gary, I think you should buy the new antenna, tell us if it works. It's only what... 2 hours of diesel on your engines?
 
Hi Mike

Just what I've heard about hookers. I only know about whoring information technology consulting services, nothing else.

When capturing using the Virtual DVHS application, the default recording and playback channel number (open the stats drawer) defaults to 63. Should be zero. If you don't change it to zero, nothing happens when you click the record button.

For playback, get a copy of Videolan. Videolan can playback darned near anything, including the stream format. Install Videolan into the Applications folder. When you click the preview (something like that) button in the AVC Browser, it will try to open Videolan, but only if it finds the app in the Applications directory. I do my captures with Videolan running in preview mode.

Quicktime can't play back the mt2 file since it's an MPEG transport file. Wikipedia has a good explanation of MPEG transport streams. The M2T is just a capture file of the stream falling out of the cable box's firewire port. You need to "unpack" the stream to use it as regular MPEG 2.

To convert from the MPEG transport format to MPEG 2 get a copy of MPEG Streamclip. You can then encode for the iPhone, iPod, or burn to a DVD.

Best regards,
Frank
 
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